Hasil untuk "Applications of electric power"

Ioannis Hadjipaschalis, A. Poullikkas, V. Efthimiou

Md. Safayatullah, M. Elrais, Sumana Ghosh et al.

Wide-scale adoption and projected growth of electric vehicles (EVs) necessitate research and development of power electronic converters to achieve high power, low-cost, and reliable charging solutions for the EV battery. This paper presents a comprehensive review of EV off-board chargers that consist of ac-dc and dc-dc power stages from the power network to the EV battery. Although EV chargers are categorized into two types, namely, on-board and off-board chargers, it is essential to utilize off-board chargers for dc fast and ultra-fast charging so that volume and weight of EV can be reduced significantly. Here, we discuss the state-of-the-art topologies and control methods of both ac-dc and dc-dc power stages for off-board chargers, focusing on technical details, ongoing progress, and challenges. In addition, most of the recent multiport EV chargers integrating PV, energy storage, EV, and grid are presented. Moreover, comparative analysis has been carried out for the topologies and the control schemes of ac-dc rectifiers, dc-dc converters, and multiport converters in terms of architecture, power and voltage levels, efficiency, bidirectionality, control variables, advantages, and disadvantages which can be used as a guideline for future research directions in EV charging solutions.

Ahmed Aghmadi, Osama A. Mohammed

Energy storage systems are essential in modern energy infrastructure, addressing efficiency, power quality, and reliability challenges in DC/AC power systems. Recognized for their indispensable role in ensuring grid stability and seamless integration with renewable energy sources. These storage systems prove crucial for aircraft, shipboard systems, and electric vehicles, addressing peak load demands economically while enhancing overall system reliability and efficiency. Recent advancements and research have focused on high-power storage technologies, including supercapacitors, superconducting magnetic energy storage, and flywheels, characterized by high-power density and rapid response, ideally suited for applications requiring rapid charging and discharging. Hybrid energy storage systems and multiple energy storage devices represent enhanced flexibility and resilience, making them increasingly attractive for diverse applications, including critical loads. This paper provides a comprehensive overview of recent technological advancements in high-power storage devices, including lithium-ion batteries, recognized for their high energy density. In addition, a summary of hybrid energy storage system applications in microgrids and scenarios involving critical and pulse loads is provided. The research further discusses power, energy, cost, life, and performance technologies.

D. Qiu, Yi Wang, Weiqi Hua et al.

A. Bouzid, J. Guerrero, A. Chériti et al.

W. He, M. King, Xing Luo et al.

Abstract Current power systems are still highly reliant on dispatchable fossil fuels to meet variable electrical demand. As fossil fuel generation is progressively replaced with intermittent and less predictable renewable energy generation to decarbonize the power system, Electrical energy storage (EES) technologies are increasingly required to address the supply-demand balance challenge over a wide range of timescales. However, the current use of EES technologies in power systems is significantly below the estimated capacity required for power decarbonization. This paper presents a comprehensive review of EES technologies and investigates how to accelerate the uptake of EES in power systems by reviewing and discussing techno-economic requirements for EES. Individual EES technologies and power system applications are described, which provides guidance for the appraisal of specific EES technologies for specific power system services. Plausibly required scales and technology types of EES over different regions are then reviewed, followed by discussions on storage cost modelling and predictions for different EES technologies. Opportunities and challenges in developing scalable, economically viable and socio-environmental EES technologies are discussed. The paper explores EES's evolving roles and challenges in power system decarbonization and provides useful information and guidance on EES for further R&D, storage market building and policy making in the transition to zero-carbon power systems.

Xingguo TAN, Chaomeng LI, Gaoming FENG et al.

To address the issue of low transmission efficiency in dual active bridge (DAB) converters during electric vehicle charging and discharging processes, a minimum current stress optimization control strategy combining the differential extremum method with segmented control is proposed. This strategy effectively optimizes current stress and suppresses backflow power under soft-switching constraints, thereby significantly improving transmission efficiency. Firstly, taking forward power transmission as an example, the conditions for achieving zero voltage soft-switching for all switches in two operation modes under extended phase shift (EPS) control are derived, and the mechanism of backflow power generation is analyzed, elucidating how reducing current stress contributes to its suppression. Subsequently, the optimization phase-shift combinations for minimum current stress are derived using the differential extremum method, and a segmented control scheme is implemented based on the soft-switching ranges of different modes. Finally, experimental results demonstrate that when the voltage conversion ratio is greater than 1, the proposed strategy achieves soft-switching for all switches across the full power range, while effectively reducing current stress and suppressing backflow power, leading to a significant improvement in transmission efficiency. However, when the voltage conversion ratio is less than 1, while current stress is still reduced, zero voltage switching cannot be achieved for all switches.

F. V. Perevoshchikov, V. G. Bukreev

Currently, the development of new control approaches for asynchronous electric drives with stringent requirements for vibration-acoustic performance and spectral composition of autonomous inverter output currents represents a highly relevant research challenge. The key challenges in designing this class of electric drives stem from the relatively low effectiveness of existing technical solutions. This limitation arises either from constraints in current controller synthesis methods or from rigorous demands regarding power-to-weight and dimensional parameters. This paper presents an original method for generating control signals in an alternating current electric drive autonomous inverter. The proposed approach utilizes regulation based on the deviation of the generalized output voltage vector amplitude in the autonomous inverter. The synthesis procedure for such a controller begins with defining the desired closed-loop system transfer function. The system dynamic processes are determined by a characteristic polynomial that can be of arbitrary type. For comparative analysis, two controller types are examined: one based on a Butterworth filter and another utilizing a Newton polynomial. The study proposes employing bilinear transformation to implement the derived continuous functions in discrete form, enabling software implementation in Simulink and subsequent microprocessor-based execution. The developed model, which accounts for discrete control signal generation, has yielded the spectral composition of the drive converter output currents and voltage-frequency characteristics under parametric disturbances introduced by the control object. Results demonstrate that the Butterworth filter-based controller shows superior efficiency compared to both open-loop systems and closed-loop systems with Newton polynomial-based controllers. The obtained results can be effectively applied in the development of low-noise electric drives for specialized applications.

O.A. Zamkova, A.O. Koshelenko

Мета роботи. Оцінити спроможність дахової фотоелектричної станції (ФЕС) забезпечити роботу інженерних мереж багатоквартирних житлових будинків, визначити комплекс заходів, які забезпечать ефективну інтеграцію дахових фотоелектростанцій з позицій досягнення нормативних показників енергетичної ефективності та мінімізації кліматичного впливу. Методи дослідження. Використано розрахунково-аналітичні методи визначення енергоспоживання житлових будівель, а також методику розрахунку електричних навантажень багатоквартирних будинків для оцінки змін електроспоживання при різних варіантах обладнання систем кліматизації, застосовано метод сценарного аналізу та енергетичного моделювання. Отримані результати. Дахові фотоелектричні станції, оснащені сучасними фотоелектричними модулями та інверторним обладнанням, розміщені на багатоквартирних п’ятиповерхових будівлях типового планування, здатні упродовж року покрити енергоспоживання систем кліматизації, що відповідає вимогам досягнення операційної кліматичної нейтральності. У роботі виконане комплексне моделювання взаємного впливу типів систем кліматизації будівель, вибору джерела енергії, температурних режимів системи опалення, фактичних температур оточуючого середовища на досяжний рівень енергетичної ефективності типових будівель житлового фонду. Моделювання режимів роботи дахової сонячної електростанції та порівняння очікуваного обсягу генерації електричної енергії з електроспоживанням типових будинків після комплексної термомодернізації і запровадження систем кліматизації з тепловими насосами дозволило встановити досягнення показників   Встановлено, що комплексна термомодернізація типових п’ятиповерхових будівель з переходом на електроопалення з використанням теплових насосів в якості основного джерела теплової енергії, дозволяють забезпечувати електроспоживання систем кліматизації будинків даховими фотоелектричними станціями. Наукова новизна. У роботі обґрунтовано комплекс енергоефективних заходів, які включають встановлення дахових фотоелектричних станцій та дозволяють досягти показників операційної кліматичної нейтральності для типових п’ятиповерхових багатоквартирних  житлових будинків. Встановлено, що перехід на електроопалення з використанням  теплових насосів в якості основного джерела енергії, дозволяє в умовах фактичних осереднених температур зовнішнього повітря знизити споживання електричної енергії в 1,8-2,0 рази при існуючих температурних режимах системи опалення. Перехід на низькотемпературні графіки роботи систем опалення житлових будинків дозволяє знизити електроспоживання у 2,8-3,2 рази порівняно з прямим електроопаленням і забезпечити вихід на показники операційної кліматичної нейтральності систем кліматизації будинків. Практична цінність. Результати можуть бути використані при розробці проєктів повної або часткової модернізації багатоквартирних житлових будівель, новому будівництві та при проєктуванні систем електроопалення будівель у тому числі з використанням електричної енергії, отриманої від дахових ФЕС. Отримані рішення відповідають ключовим задачам Енергетичної стратегії України до 2035 року, сприяють зміцненню енергетичної безпеки України, виконанню міжнародних зобов’язань в частині скорочення споживання первинних енергетичних ресурсів, зниження викидів парникових газів.

Dileep Kumar Kana Padinharu, Guang‐Jin Li, Guang‐Bo Zhang et al.

ABSTRACT This paper proposes a Vernier machine with an improved stator design that adopts open stator slots and permanent magnets installed on both the rotor and stator. Compared to an existing Vernier machine in the literature, referred to as Design 1, the exclusive stator slots for permanent magnets in the proposed machine help mitigate demagnetisation issues by physically isolating the windings and the magnets. Additionally, the open stator slot design facilitates the installation of form‐wound coils which is desirable for large generators used in direct‐drive wind power applications. Using 2‐dimensional finite element analysis, the proposed design is compared with a conventional surface‐mounted permanent magnet machine, a conventional Vernier machine and Design 1. The findings indicate that the proposed Vernier machine uses both odd and even harmonics to generate torque, and it can exhibit superior electromagnetic performance, including torque and efficiency, compared to the conventional surface‐mounted permanent magnet machine and conventional Vernier machines and demonstrate comparable electromagnetic performance to Design 1. Furthermore, to enhance the torque‐to‐mass ratio of the proposed Vernier machine, through‐slots below the stator magnets are introduced and found to be effective without significantly compromising torque and efficiency. The simulations have been validated by experiments based on a prototype.

Yue Shen, Feng Yang, Jianbang Wu et al.

The global transition toward sustainable and intelligent farming has positioned Electrified Agricultural Machinery (EAM) as a central focus in modern equipment development. By integrating advanced electrical subsystems, high-efficiency powertrains, and intelligent Energy Management Strategies (EMSs), EAM offers considerable potential to enhance operational efficiency, reduce greenhouse-gas emissions, and improve adaptability across diverse agricultural environments. Nevertheless, widespread deployment remains constrained by harsh operating conditions, complex duty cycles, and limitations in maintenance capacity and economic feasibility. This review provides a comprehensive synthesis of enabling technologies and application trends in EAM. Performance requirements of electrical subsystems are examined with emphasis on advances in power supply, electric drive, and control systems. The technical characteristics and application scenarios of battery, series hybrid, parallel hybrid, and power-split powertrains are compared. Common EMS approaches (rule-based, optimization-based, and learning-based) are evaluated in terms of design complexity, energy efficiency, adaptability, and computational demand. Representative applications across tillage, seeding, crop management, and harvesting are discussed, underscoring the transformative role of electrification in agricultural production. This review identifies the series hybrid electronic powertrain system and rule-based EMSs as the most mature technologies for practical application in EAM. However, challenges remain concerning operational reliability in harsh agricultural environments and the integration of intelligent control systems for adaptive, real-time operations. The review also highlights key technical bottlenecks and emerging development trends, offering insights to guide future research and support the wider adoption of EAM.

Bartosz Uniejewski

Accurate day-ahead electricity price forecasts are critical for power system operation and market participation, yet growing renewable penetration and recent crises have caused unprecedented volatility that challenges standard models. This paper revisits variance stabilizing transformations (VSTs) as a preprocessing tool by introducing a novel parametrization of the asinh transformation, systematically analyzing parameter sensitivity and calibration window size, and explicitly testing performance under volatile market regimes. Using data from Germany, Spain, and France over 2015-2024 with two model classes (NARX and LEAR), we show that VSTs substantially reduce forecast errors, with gains of up to 14.6% for LEAR and 8.7% for NARX relative to untransformed benchmarks. The new parametrized asinh consistently outperforms its standard form, while rolling averaging across transformations delivers the most robust improvements, reducing errors by up to 17.7%. Results demonstrate that VSTs are especially valuable in volatile regimes, making them a powerful tool for enhancing electricity price forecasting in today's power markets.

Konstantin V. Arnautov, D. Akimov

In recent years, the field of large language models (LLM) has been actively developing, finding more and more applications in various branches of knowledge and spheres of activity. At the same time, the potential of using LLMs in the electric power industry has not been sufficiently explored to date. This paper considers the creation of autonomous agents based on LLMs for optimization of electric power system modes. The principal possibility of building an engineering decision support system to ensure acceptable values of the electric power system mode parameters using LLM is shown.

Leone Martellucci, Roberto Capata

One of the most critical issues in electric vehicle engineering concerns the thermal management of the battery pack, especially in high-performance applications, which are increasingly demanded by the market. Very interesting, from this point of view, is the study of motorsport applications, almost always characterized by a high ratio between power output and energy stored in the battery pack, which makes the problem of thermal management particularly important. It should be noted that motorsports applications typically have a particularly demanding trend of current discharging and charging from the battery pack, with numerous positive and negative peaks at high c-rates; this obviously produces, due to the Joule effect, a much higher amount of heat per kWh than in conventional road cars and therefore makes efficient and high-performance thermal management very important. In this work was defined, analyzed and optimized an innovative mixed solution with forced air cooling and PCM material (phase change material) for high performance battery modules with cylindrical cells used in a Formula Student car. In the various battery thermal management technologies, Air cooling is one of the most used solutions and can be successfully integrated with PCM cooling technique. In the work proposed here, the optimization and numerical simulation of different solutions and configurations is described. The target parameters considered are: airflow rate, cell spacing and mass of PCM. Fluid dynamic simulations were used to identify the optimal value of the radial gap between the cells, a fundamental construction parameter, and the speed of the air coming out of the fans. The choice of the mass of the PCM sheets was made on the basis of the quantity of heat to be removed to obtain a significant effect on the final temperature of the cells during the test (<50°C) and compatibly with the spaces available between the modules inside the battery pack. The simulations of the optimal solution will be compared to experimental results for validation, by the realization of the most promising configuration and its real experimentation on the car, in order to validate the expected performance of the thermal management system.

Tarraf Mokhammad, V. V. Gayevskiy, Deeb Mukhammad

Among several typical energy storage methods, that flywheel energy storage has advantages such as high instantaneous power, high-performance and long service life, making it perfect secondary energy storage technology for traditional internal combustion engine vehicles. Although some progress has been made in the applied research of flywheel energy storage technology, there are no detailed studies at home and abroad that summarize its application in the vehicle applications. This paper searches the data on «flywheel energy storage», analyzes the research progress of flywheel energy storage in automotive industry, and analyzes the research progress of flywheel energy storage in vehicle applications. The search data show that flywheel energy storage technology for the vehicle applications has been studied for the last 20 years, although it is a niche research area. With respect to two typical flywheel hybrid systems, namely electric and mechanical drive, we have focused on the history of the study, research and validation of mechanical flywheel hybrid system in the automotive industry, as well as the structural characteristics of this system, the current state of research and future research trends.

FU Xiaobiao, HOU Jiaqi, LI Baoju et al.

Weather classification is an indispensable preprocessing step in photovoltaic (PV) power prediction. A new two-modal weather classification methods based on PV power clustering was proposed to finely depict the uncertainty of PV power output. Both PV power data and meteorological data were considered for weather classification, providing a novel and effective path for PV power prediction. In addition, data fusion technology was used to extract relevant information from both numeric weather prediction (NWP) data and measured meteorological data to help for weather classification. This approach reduces the model’s reliance on the accuracy of forecasted meteorological indicators and improve the robustness of the model. Experiments based on data from a PV power station in Jilin demonstrated the rationality of the proposed weather classification method. Combining the PV power probability prediction with the proposed weather classifier resulted in prediction interval coverage probabilities closer to the preassigned confidence level and narrower mean prediction interval width.

Piotr Kuwałek, Grzegorz Wiczyński

Low-frequency disturbances of power quality are one of the most common disturbances in the power grid. These disturbances are most often the result of the impact of power electronic and energy-saving devices, the number of which is increasing significantly in the power grid. Due to the simultaneous operation of various types of loads in the power grid, various types of simultaneous disturbances of power quality occur, such as voltage fluctuations and distortions. Therefore, there is a need to analyze this type of simultaneous interaction. For this purpose, a special and complementary laboratory setup has been prepared, which allows for the examination of actual states occurring in modern power networks. Selected research results are presented for this laboratory setup, which determine its basic properties. Possible applications and possibilities of the laboratory setup are presented from the point of view of current challenges.

LIU Hui, LUO Wei, SU Yi et al.

The frequency stability of the wind power grid-connected system may be improved by the participation of wind turbines in frequency regulation. However, it is difficult for the existing droop control to coordinate the frequency response characteristics and the operating state of the wind turbine. An adaptive droop control strategy is proposed to make full use of the rotor kinetic energy to participate in frequency regulation and ensure the stable operation of the wind turbine considering the rate of change of frequency (ROCOF) and the rotor kinetic energy. Firstly, a coupling function between the droop coefficient and ROCOF is established by the piecewise function with the intervals of ROCOF according to the system frequency, which can be released to ensure more energy from wind turbines at the initial stage of the disturbance. In this condition, the frequency drop is slowed down due to the support of the wind turbine for frequency regulation. Besides, to avoid the over-deceleration of the wind turbine and secondary frequency drop, an influence factor on the rotor speed is introduced to adjust the droop coefficient according to the operating state of the wind turbine. Finally, a wind-thermal combined system simulation model is built on the MATLAB/Simulink platform to verify the effectiveness of the proposed control strategy. The simulation results show that the proposed strategy can effectively apply the rotor kinetic energy of the wind turbine to improve the frequency response characteristics of the system while ensuring the stability of the wind turbine speed.

Qiong Wu, Haiyun Luo, Hao Wang et al.

A novel Hydrodynamic Cavitation-Assisted Oxygen Plasma (HCAOP) process, which employs a venturi tube and oxygen injection, has been developed for enhancing the production and utilization of hydroxyl radicals (·OH) in the degradation of organic pollutants. This study has systematically investigated the fluid characteristics and discharge properties of the gas–liquid two-phase body in the venturi tube. The hydraulic cavitation two-phase body discharge is initiated by the bridging of the cavitation cloud between the electrodes. The discharge mode transitions from diffuse to spark to corona as the oxygen flow rate increases. The spark discharge has the highest current and discharge energy. Excessive oxygen results in the change of the flow from bubbly to annular and a subsequent decrease in discharge energy. The effects of cavitation intensity, oxygen flow rate, and power polarity on discharge characteristics and ·OH production were evaluated using terephthalic acid as a fluorescent probe. It was found that injecting 3 standard liter per minute (SLPM) of oxygen increased the ·OH yield by 6 times with only 1.2 times increase in power, whereas<0.5 SLPM of oxygen did not improve the ·OH yield due to lower breakdown voltage. Negative polarity voltage increased the breakdown voltage and ·OH yield due to asymmetric density and pressure distribution in the throat tube. This polarity effect was explained by numerical simulation. Using indigo carmine (E132) as a model pollutant, the HCAOP process degraded 20 mg/L of dye in 5 L water within 2 min following a first-order reaction. The lowest electric energy per order (EEO) was 0.26 (kWh/m3/order). The HCAOP process is a highly efficient flow-type advanced oxidation process with potential industrial applications.

Ruiyun Fu, Mary E. Lichtenwalner, Thomas J. Johnson

With the increasing installations of solar energy, electric vehicles, and other distributed energy resources and the deeper developments of digitalization and standardization, cybersecurity became more and more essential and critical in modern power systems. Unfortunately, most prior research work focuses on the cybersecurity of power transmission and distribution networks other than distributed energy devices and their grid-connected power converters. Focusing on the Grid-Connected Power Electronics Converters (GCPECs), this article does a comprehensive review of existing outcomes from selected references, in the aspects of vulnerabilities, countermeasures, and testbeds. By analyzing the GCPEC&#x2019;s layout and countermeasure candidates, it is found that the vulnerabilities of GCPECs include both cyber and physical layers that are easily accessible to malicious hackers. These vulnerabilities in the two layers must be considered simultaneously and coordinate well with each other. Especially, hardware hardening is an essential approach to enhance cybersecurity within GCPECs. It is also noticed that the detection and mitigation approaches should consider the complexity of algorithms to be applied and assess the limits of computing and data processing capabilities in GCPECs while evaluating the feasibility of countermeasure candidates to cyberattacks in testbeds. In addition, the countermeasures should meet relevant standards, such as IEEE-1547.1, IEEE-2030.5, IEC-61850, and IEC-62351, to ensure the interoperability and cybersecurity of GCPEC devices in smart grids. Finally, based on the review and analysis, four recommendations are raised for future research on GCPEC&#x2019;s cybersecurity and their applications in smart grids.